assume cs:codesg,ds:datasg

datasg segment
db 'BaSiC'
db 'iNfOrMaTiOn'
datasg ends
codesg segment
start :mov ax,datasg
       mov ds,ax
       mov bx,0
       mov cx,5
     s:mov al,[bx]
       and al,11011111B
       mov [bx],al
       inc bx
       loop s
       mov bx,5
       mov cx,11
    s0:mov al,[bx]
       or al,00100000B
       mov [bx],al
       inc bx
       loop s0

       mov ax,4c00h
       int 21h
codesg ends
end start

